Recently, due to the advantages of high contrast, fast response time, high transmittance, and so on, vertical alignment (VA) liquid crystal technology has been widely used.
Typically, each pixel of the VA liquid crystal is divided into two regions, wherein one region (main-region) is the same with an ordinary pixel, and another region (sub-region) generates a voltage difference to the first region through circuit designs, the wide viewing angle performance of the VA liquid crystal is thereby improved. A pixel with such design is typically adopting two scan lines, wherein a first scan line charges normally to the two regions, respectively, a second scan line controls a TFT for charge sharing in the sub-region, such that the voltage difference between two pixel electrodes in the two regions is obtained.
Since the two scan lines occupied a partial space, and reduce the aperture ratio, therefore in the subsequent improvement, the second scan line is merged into the scan line of a next stage pixel, so as to improve the aperture ratio. However, under this design, the two scan lines cannot be opened at the same time, otherwise the voltage difference between the main-region and the sub-region cannot be generated, hence the purpose of improving the viewing angle cannot be achieved. In view of the GOA circuit designs to the existing large-size panel, due to the electrical load and other factors, the circuit is generally adopts multi-clock signals design such as fourth clock signals, sixth clock signals, or even eighth clock signals, such that the waveforms of current stage scanning signals between two adjacent stages are overlapped, as shown in FIG. 1, which means that the scan lines of two adjacent stages will both turn on at the same time, it is hardly to meet the driving demand for the VA liquid crystal with wide viewing angle as mentioned above.